21852317 has 2 divisors, whose sum is σ = 21852318. Its totient is φ = 21852316.

The previous prime is 21852307. The next prime is 21852343. The reversal of 21852317 is 71325812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19945156 + 1907161 = 4466^2 + 1381^2 .

It is a cyclic number.

It is not a de Polignac number, because 21852317 - 2¹⁰ = 21851293 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21852317.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21852307) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10926158 + 10926159.

It is an arithmetic number, because the mean of its divisors is an integer number (10926159).

Almost surely, 2^21852317 is an apocalyptic number.

It is an amenable number.

21852317 is a deficient number, since it is larger than the sum of its proper divisors (1).

21852317 is an equidigital number, since it uses as much as digits as its factorization.

21852317 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3360, while the sum is 29.

The square root of 21852317 is about 4674.6461898201. The cubic root of 21852317 is about 279.5755345788.

The spelling of 21852317 in words is "twenty-one million, eight hundred fifty-two thousand, three hundred seventeen".